Reversible hydraulic pump and turbine transmission



July 14, 1953 G. H. CARTER 2,645,086

REVERSIBLE HYDRAULIC PUMP AND TURBINE TRANSMISSION Filed Dec. 16, 1948 2 Sheets-Sheet l July l4, 1953 G. H. CARTER 2,645,086

REVERSIBLE HYDRAULIC PUMP AND TRBINE TRANSMISSION Filed Dec. 1 6, 1948 2 Sheets-Sheet 2 INVENTOR. fo/asf 64,975@

mitted from the engine to the wheels.

Patented July 14, 1953 UNITEDv sTATEs PATENT OFFICE REVERSIBLE HYDRAULIC PUMP AND TURBINE TRANSMISSION George H. Carter, Port Washington, N. Y. Y

Application December 16, 1948, Serial No. 65,665

(C1. (so-,54)

8 Claims.

vFor example, the engine is not as effectively usable as a brake. Furthermore, with the ordinary fluid drive, the acceleration isrslowwhen startingor driving against heavy resistance. In accordancewith the present invention a .positive flow-of fluid is produced which enables the power of the engine to bemore effectively applied under adverse conditions. Also the drive may be adjusted so as to produce a true neutral condition when desired so that no -power is trans- ',Ihe drive may be adjustedso as to reverse the flowthereby enabling the engine to act as an effective brake.

The general objects of the invention are to overcome the defects indicated and other defects of existing fluid drives and to provide a drive which is positive in action, capable of being put A into effective neutral condition and capable of producing a proper braking action. Y As aresult the vehicle is always under the complete control of the driver., y i

Other objects and advantages of the invention will appear in the course of the following description of one preferred embodiment thereof. In the accompanying drawings which show a 'preferred embodiment of the driveas adapteur@ an automobile transmission:

Figure 1 is an end view, of the drive casing;

i Figure 2 is a vertical longitudinal section of the drive on line 2-2 of Fig. 1;

. Figure 3 is a horizontal section of a part of the drive taken on line 3-3 of Fig. 2;

Figurejl is a transversesection through a part vof the drive taken on line 4 4 of Fig. 2; f

y Figure 5 is a transverse vertical section of the drive taken on line 5--5 of Fig. 2;

, Figure 6 is a similar section taken on line 6-6 of Fig. 2;

Figure 7 is a similar section of the lower part vof the drive taken on line 'l--l of Fig. 2; p y Figure 8 is a fragmentary face view of a part -as to` rotate yfreely therein, but to nt closeV of the rotary distributor, partly in sectionon line 8-8 of Fig. 2; and

Figure 9 is a fragmentary view similar to Fig. 5 showing the valves in neutral position.

Referring to .the drawings in detail 2|] is the driving shaft which may be considered as an extension of the crank shaft of an internal combustion engine, not shown. 22 is the driven shaft which may be considered as the propeller `shaft offa motor vehicle which is geared through the usual differential, not shown; to the vehicle driving wheels. 24 is a suitable fluidtight casing which is mounted upon the vehicle frame and bolted' to the engine, or otherwise Xed upon the with an inlet opening 38 and a discharge openingk 40; The inlet opening is governed by an inlet vvalve 42 which is shown as a plug valve rotating ina cylindrical chamber 44 and having a cut-out part 46. The discharge valve 48 is of similar construction and ,has a cut-out portion 50. These two valves are preferably provided with voperating levers 52 which are connected by a link 54 so that the two valves will rotate together. y

kThe discharge from the pump when in normal operation passesthrough a duct into a circular chamber 53 surrounded by an annular wall 64 .which forms a part of the casing. Y Keyed to the end of shaft 20 is a rotary distributor 1D which has` a neckl portion 12 fitting against the end of the wall 64 and preferably provided with flange 'I4 fitting within the wall so enough tokprevent substantial leakage between the wall andthe neck.v 'Ihe distributor 10 has Yanouter .wall 12 to which the neck is attached, ,and an inner wall 14. These Walls are connected near their peripheral portions by webs or varies 16 which extend from the outer margin of the distributor inward in a general radial direction for a part of the diameter of the distributor, for example, about one-third of the way in towards the center. The wallsv 'l2and 14 of the distrib- ,utor curve at their ,peripheries into portions parallel-With the axis of the shaft 20, and the webs TS are similarly curved so as to produce an annular series of discharge openings 'I8 at the outlet face 80 of the distributor. The outer portions of the webs are inclined, as clearly shown at 82 in Fig. 4, so as to discharge the liquid flowing between them in an angular direction to the aXis of rotation of the distributor, the liquid being directed forwardly in the direction of rotation. The liquid thus issues in the form of a plurality of forwardly inclined jets. It will be seen that the liquid is forced through the distributor from the outlet orifice 60 of the pump through the space surrounded by Wall 64 and the neck 12 of the distributor.

The inner wall i4 of the distributor is shown as suitably curved so as to promote a streamlined flow of the liquid, and affixed to its outer face is a filler plate 84 which provides the distributor with a substantially plane face 80. The space between the wall 'I4 and the plate 84 is merely a void space. The distributor 12 rotates inside of a shell 86 constituting a part of the casing 24.

The shaft 20 rotates in a suitable bearing 90 in the wall of the casing, such bearing being shown as provided with an oil catching groove 92 provided with a drain passage 94 leading to the casing adjacent to the pump inlet opening 38. As such region is always under negative pressure due to the action of the pump, any oil leakage will be drawn back into the pump and will not escape to the outside of the casing.

The opposite side of the casing from the pump chamber is closed by removable wall which has a bearing portion |02 in which the driven shaft 22 rotates. On the end of the shaft 22 is keyed a turbine rotor |04 which has formed through its peripheral portion a plurality of fluid passages |00 separated by turbine blades |08. The turbine blades are preferably equal in number and spacing to the webs 82 in the distributor. They are preferably provided with concave faces I0 and with angularly shaped backs having Wall portions ||2 inclined at about the same inclination as the inclination of the webs 82, and wall portions ||4 inclined at an opposite but less inclination than the walls ||2. The part of the turbine between the turbine hub and the blades is preferably a hollow or void space |20 enclosed between the flush side walls |22 of the turbine. These walls revolve in closely spaced relationship to the plate 84 and the inner wall |24 of the casing portion |00. Sufiicient clearance is allowed to provide free rotation, but otherwise is kept as low as possible so as to avoid the presence of any large body of the liquid at these points.

The casing portion |00 has a circular chamber |30 therein at the periphery of which are a plurality of fluid passages |32, separated by guide blades |34 which of course are stationary. The liquid from the chamber |30 is discharged through a port |48l and passes through a passage' |42 in the lower part of the casing to a port |44 below the pump chamber. The casing is formed with a wall |46 enclosing the lower part of the pump chamber and a wall |48 enclosing the upper part of the pump chamber. Between the wall 35 of the pump chamber and wall |46 is a passage |50 through which the liquid passes from the port |44 to the inlet opening 38 of the pump.

When the valves 42 and 48 are set in normal operating position, as shown in full lines in Fig. 5. the liquid is discharged by the pump through the opening 40 and passes through the duct 60 and through the distributor neck and is forced out between the Webs 82. This liquid impinges upon the curved faces |I0 of the turbine blades |08, and is discharged from the turbine blades against guide blades |34 and from thence passes into the chamber |30, through the port |40, passage I42, port |44, passage |50 and back to the pump through the inlet opening 38.

When the valves 42 and 48 are shifted to reverse position, as shown in dotted lines in Fig. 5, then the liquid discharged by the pump passes out ofthe opening 40 and is directed by the valve 48 through the passage |52 between the pump chamber wall and the casing wall |46 to the port |44. The liquid cannot pass through the passage |50 because this is now closed at its upper end by the valve 42. The liquid passes from the port |44 through the passage |42 in reversed direction and into the chamber |30 and is discharged between the stationary blades |34 against the inclined surfaces I4 on the backs of the turbine blades. The liquid passes between the distributor webs in reverse direction out through the neck 12 and duct 60 into a passage |54 between the pump chamber wall and wall |48. It passes from the passage |54 through the valve 42 and into the inlet opening 38. In this valve setting the valve 48 closes the opening from the discharge opening 40 to the duct 60.

When the valves are set for normal operation in the position shown in full lines in Fig. 5, it will be seen that the liquid is positively discharged by the gear pump into the rotary distributor 10 and is forcibly discharged between the webs or veins of the latter against the curved faces ||0 of the turbine blades from which the liquid under pressure issues between the fixed guide blades |34. This forcible now of the liquid between the turbine blades tends to cause the turbine to rotate in the same direction as the distributor so as to rotate shaft 22 in the same direction as the driving shaft 20. When the engine is going slowly, the rotation of the pump gears and of the distributor is also slow and the force applied to the turbine is small. Until this force becomes sufficient to overcome the resistance to rotation of the shaft 22, this shaft and the turbine will not move, and the vehicle will remain stationary or approximately so. As the speed of the engine is increased the pressure of the liquid discharged by theV gear pump is increased, and the rate of rotation of the turbine will increase. Eventually, asfor example when the vehicle is driven along a level road, the speed of the turbine will increase until it is the same or approximately the same as the speed of rotation of the distributor. At this point a condition of direct drive from the driving shaft to the driven shaft will obtain. If increased resistance to movement of the vehicle occurs, as for example in climbing a hill, then the speed of rotation of the shaft 22 will Vbe decreased, and there will be slippage between the turbine and the distributor with corresponding increase in force applied so as to overcome the resistance of climbing the hill.

Where the vehicle is driven on a level road. or a slight down grade, and this condition obtains for a sufficient distance, the power required may decrease to a point where the turbine rotor will be driven faster than the distributor so that the eifect of an overdrive is obtained.

Owing to the fact that the gear pump is a positive acting pump which will pump a definite volume of liquid depending upon the speed. of

rotation ofthe shaft 2U, it is V'possible'tosecure a definite accelerating action of the transmission.

In other words, the power delivered will increase with the acceleration of the engine and the driver can produce such4 acceleration of the car as 'the engine is capable:ofproducing-.as i in the case of an ordinary gear transmission. There is not the lag over which the driver has no control as in the case of the ordinary fluid drives now in use.

- When the valves are moved to reverse position, as shown in dotted lines in Fig. 5, lthen the circulation from the pump is reversed, as

already described. The fluid will be forced posi- Ytively against the backsy of the turbine blades so that the turbine will be retarded in its rota- -`tion and will clearly oppose the rotation of shaft 22.

Fig. 9v where it will be seen that both valves are partly open so that the liquid pumped by Y .the pump will merely be circulated through the passages |54, |52 and 1'50 from the discharge opening 40 to the inlet opening 38. There will -thus be no pressure through the turbine and any slight flow which may take place through nthe distributor and turbine and normal operating passages will be negligible and will apply no substantial force to the turbine and driven shaft. There is thus no creeping effect produced as is the case with the usual fluid transmissions. In case there should be any tendency for the rotation of the distributor to build up small pressures in the turbine by reason of centrifugal action, this may be neutralized by setting the valves slightly beyond mid-position in the direction of reverse position as indicated in dotted lines in Fig. 9 so that there will be a very slight reverse pressure upon the turbine which will counteract any centrifugal effect.

It will be seen that the whole system is enclosed in the fluidtight casing 24 so that there will be no substantial loss of liquid. `Such leakage as takes place from the pump and between the adjacent surfaces of the distributor, turbine and casing portion will accumulate in the bottom of the casing as indicated at |10 so that the lower part of the casing constitutes a liquid reservoir. Leading down to this reservoir from the pump inlet is a pipe |12 at the lower end of which is an upwardly opening check valve |14. As soon as there is any loss of liquid from the system through which the liquid normally flows, there will be a slight vacuum created by the pump and sufcient liquid will be drawn up through the check valve to replenish the supply and keep the circulating system completely filled at all times.

While I have illustrated and described in detail certain preferred forms of my invention, it is to be understood that changes may be made therein and the invention embodied in other structures. I do not, therefore, desire to limit myself to the specific constructions illustrated, but intend to cover my invention broadly in whatever form its principle may be embodied.

I'claim: f- :Lf v-.1. A fluid transmission comprising l angear pump having rotary gearsand a ystationary casing, at least one of said gears being-connected to a source of power, a rotary fluid distributor connected to rotate withan element of the gear pump, a turbine connected with adriven member, a fixed varied member adjacenttojthat' part vof the turbine constituting,.=the.outlet .during forward operation, and a closed fluidcirculatory .system Lthrough which the fluid vcirculates from `the pump throughY the` distributor, turbine and -vaned member and back to the pump,` saidcirlculatory system including duct means of f such .capacity as to carry the entire .body of fiuiddehliveredby the pump to the distributor and to .return the rentire body of fluid passing through the turbine back to the pump, thecapacity ofthe 'pump-being sufficient to maintain a. continuous operative circulation of liquid' throughv the tributor, turbineandipump.

2. A fluid transmission comprising' a driving shaft, a positive flow pumpA driven thereby, a

dis-

Vrotary distributor mounted on said driving shaft ,andhaving ra pluralityy of vanes adjacenttoits periphery, said varies being inclined in ai direction to cause fluid flowing through said -distrib- `:utor tobe ejected forwardly in the direction of rotation of the distributor, a driven shaft mounted in alignment with the driving shaft, a krotary turbine having blades adjacent to its periphery receiving the fluid from said distributor, a stationary member' mounted on the `other .side of said turbine from said/distributor havingfguidc f, varies receiving fluid from the bladeson theV turbine, land a. closed fluid :circulating system through which the fluid flows from the pump Vthrough the distributor, turbine and vaned memberand back to the pump, said circulatory system including duct means of such capacity as to carry the entire body of fluid delivered by the in which the distributor comprises a pair of spaced circular walls with the vanes between them, the vanes extending part way towards the center of the distributor.

distributor having spaced walls'connected by varies so as to provide discharge paths inclined in the direction of rotation of the distributor. a casing portion enclosing said distributor. a driven shaft, a turbine disc mounted on'said driven shafty and rotating in said casing portion adjacent said distributor, said turbine having blades near the periphery receiving fluid discharged from between l l? the vanes of the distributor, said casing having a sholiow portion adjacent to said turbine, said hol- -low portion containing xed guide vanes receiving'fiuid discharged from between the blades of vtheturbine' and means for conducting the duid discharged by said guide vanes back to the pump. A fluid transmission comprising a fixed casing having a pump compartment, a driving shaft :passing throughA the'said compartment, a gear :pump in said pump compartment, one element -.of :which isfxed to said driving shaft, a hollow :"disc-like distributor mounted on said driving shaft,l said distributor having spaced walls con- ;nected by vanes extending to the periphery of thedstributor so as to rprovide discharge paths inclined in thedirection of rotation-of the distrib- ,.utor; a casing portion enclosing said distributor, apdriven shaft, a turbine disc mounted on said tdriven shaft and rotating in said casing portion adjacent said distributor, lsaid turbine having blades near its peripheryzreceiving the fluid dis- .charged from between thelvanes of the distributor, said casing having a hollow portion adja- :cent to said turbine, said hollow portion contain- 'ingfixed guide vanes-receiving fluid discharged Yfrom between the blades of the turbine and means 'forconducting the fluid discharged by said guide vanes back to the pump, said pump chamber having inlet. and outlet openings, by-passes ,around the pump chamber and valves associated therewith fory reversing the vdirection of flow be- Utween .the pump and .the turbine.

8.. A fluidtransmission comprising axed cas- .ing having a pump compartment, a driving shaft -passing through saidv compartment, a gear pump .in said pump compartment, one element of which 8 is fixed to saiddriving shaft, a hollow disc-like distributor mounted on said driving shaft, said distributor having, spaced walls connected by vanes extending to the periphery of the distributor so as to provide discharge paths inclined in the direction of rotation to the distributor, a casing portion enclosing said distributor, a driven shaft, a turbine disc mounted on said driven shaft and rotating in said casing portion adjacent said distributor, said turbine having blades near the periphery receiving the fluid discharged from between the vanes of thev distributor, said casing having a hollowportion adjacent to said turbine, said hollow portion containing fixed guide vanes receiving uid discharged from between4 the blades of the turbine, and means for conducting the fluid discharged between said guide vanes back to the pump, saidfpump chamber having inlet and outlet openings, and valve means associated therewith by which the ow to the pump may be by-passed from the inlet to the outlet so as to produce a neutral condition of the transmission.

GEORGE H. CARTER.

References Cited yin the file of this patent UNITED STATES PATENTS Wirth et a1.' June 15, 1948 

